Castleberry played with Leonard in high school and college. He was previously an assistant video coordinator for the Spurs, so becoming a player development coach with Toronto is a step up.
The Raptors acquired Leonard in a trade with San Antonio over the summer. They took a big risk by dealing franchise cornerstone DeMar DeRozan and a protected first-round pick to the Spurs despite knowing that Leonard could leave as a free agent next year. Leonard reportedly has his eyes on joining the Lakers eventually. They’re hoping that he will enjoy his time with Toronto and end up signing there longterm, similar to how impending Paul George chose to stay in Oklahoma City.